Albert herzfeld



Patented Got.

Il il A.HERZFBM.

BALL GRINDING MILL.

` N0 Model.)

UNITED ALBERT HERZFELD, OF IAIALLE-ON-'lill-SAALE, GERMANY,

BALL oeinoluomrmni..

SPECIFICATION forming part of Letters Patent No. 569,828, datedctcier 2G, 1896:!

Appiimnn ned nay 3,1895. seni No'. 548,021. (no man.)

To LZZ whom, it may concern:

Be it known that I, ALBERT I-IERZFELD, a subject. of the King of Prussia, Emperor of Germany, residingat llalle-on-the-Sziale, GermenyJia-vc invented new and useful Improve- -ments in. Ball Grinding-BEUS, of which the lzo following is a. specification.

This invention relates to an improved construction of hell grinding-mills, in which the grinding vessels have not onlye rotary inotion around their own axes, but also, Simultaneously, a. motion around an zixiseccentric to those'of the vessels, so that e. planetary motion is impartedL to said vessels. l

In the accompanying drawings a' hell grinding-mill of this class is described, Figure l showing a. vertical section of a mill constructed according to my invention; and Fie'. 2 a horizontal section on line X X, Fig. 1. Fig. 3 isla Vertical section of the wellof the grinding vessels, showing the conical open'- ings on an enlarged scale.l

Similar letters of reference indicatecorrespending parte'. I

Referring tothe drawings, A represents e. Vert-ical main Shaft, around which is. rotated e horizontal frame B, preferably in the shape of o cross. In the arms of the croseshaped' frame B nre mounted'rotateble shafts ce @los a?, to the upper ends of which are firmly attached the grinding vessels C. These shafts and the vessels C are supported on o base H,

' which serves as the stepbearing for the npby thestetionery gear-wheel l" right shaft Lend to which is rigidly attached a gear-wheel F, located concentrically with the shaft A. The stationeryv gear wheel meshes with the geer-wheels z', z2, z3, and e4, which are keyed to the lowermost'ends of the shafts caf a? ci o4. By the rotation of the shaft A and the rotary motion of the cross-shaped frame B connected therewith the vessels C are placed in rotation around the shaft A end at the seine time mound their own axes and the inicrmeshing geur-wliccls ,a al 2f 2^", Suid vessel rc Ceiving at planetary motion.

The vessels C nrc preferably unido of circuler shape with flat bottom and upwardly- .iloring eide walls.. The tops of lhc vessels aire closed by coi-'ors lian-'ing central openings for the supply-pipes D. ,Below cach ot' the covers ofgthe Vessel is formed en minier Space R, which is connected with the lower part of the vessels hy openings .5, which ere formed in thevouter edge of e diaphragm l, fixed tothe Side Woll of in g a. central cone .l opening up through the cover of the vessel and downwardly into the lower port of the Sonie. The enter Well of the annuler spa-ce B. is formed hy the upper part of the outwardly-timing side Woll of the Vessel C, seid upper part being; preferably provided with small screening-openings i' r oi the, -vessel, end her conical shapefwhich are 1wider it their outer,-

than at their inner ends, es shown ele-arly in. Figs. l and 3.

The material to he ground is supplied to the Yessels C by a hopper D, that extends around the upper part of the upright shaft' A, and supply-tubes D, which connect the lower port of the hopper with the central hollow coneei .l of the vessels'. The hopper E, as well es the supply-tubes D', rotate with the upright shaft- A. in the lower port of the vesseis'C are arranged halls c c, by which 'the grinding of the mass in the Vessels is produced.

Owing to the outeerd-ilerinrr shape of the side wall-3 of the vessels, the hails are moved during the rotation of the vessels in upward dixection,'so as to more along the diaphragm I, forming the bottom of the annular Space R, into Wliichtle coinniinntcd material is gine-sed through the' slots or openings s, eo to be forced by centrifugal power through "the conical openings 'r to the outside of the Vessels C'. This screened materia-l is collected by c eesing that extends around the vessels C or in any 'other suitable manner. The slot-lilac Openings c we made of such dimensione that the'holls c c cannot pass through the seine into the annular space R. Coni-ser particles of the ground mess which cannot poss in outward direction through the screened openings in the outer weilof thc annuler space R o-re conducted into the lower part 0E the vessel (.by :t curved tubo L, which is arranged -the curved tubes L and be returned by thc inner ends of the saine into the lower part of ythe vessels C.

In the ball grinding-mill described the ac tion takes place under the influence of two separate centrifugal forces, first, that which is obtained by the rotation ofthe vessels C around the main -shaft A, and, second, that which is obtained by the rotation of the vessels C around their axes cda? ci a". The balls c c remain, therefore, always on that side of the vessels which is farthest away from the main shaft A. The proportion ot' the number of teeth of the stationary gear-wheel l" to the number of the teeth of the gear-wheels z' z2 zie" has to be so arranged in connection with the size of the vessels C that the oentrifugal force which is produced by the rotation of the vessels around the main axis is greater than the centrifugal force that is 0btained through the rotation of the vessels C around their own axcS. It is not material .whether the shafts os' d2 d3 of* are parallel to same, grinding vessels mounted on shafts ol said 'f rame, a stationary gearwhee1 below the V:supporting-frame and through the center of which said main shaft turns, gear-wheels on thcshafts of the grinding vessels intermeshing with the statonary-gear-wheel whereby a planetary motion is imparted to the-vessels around the main shaft, a diaphragm at the upper part of each Ygrinding vessel, provided with a central vhollow"cnnfr'nffning both upwardly and downwardly, 'said diaphragm, cone and the upper part of each vessel forming an annular screening-chamber communicating with the lower part of said grinding vessel by slot-like openings in the diaphragm and located near the side walls ol' the vessel, openings in the upper portions of the side walls of the grinding vessels, grinding-balls in the. lower parts of said grinding Vessels, said 'grinding-balls being of greater diameter thanv the' width ,of `the slot-like openings, means forfsupp'l ying the material to be ground into said `vessels, and curved tubes arranged in the upper part of the screening-chamber for returning the coarse particles into the main Vessels.

ln testimony whereof I have signed my name to this specicationin the presence of two subscribing witnesses.

ALBERT HERZFELD.

Witnesses: RUDOLPH FRICKE, OTTO DOEDERLEIN. 

